<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Document</title>
	<style>
		h1::before {
			content: "🔥";
			/* display: inline-block;
			width: 30px;
			height: 30px;
			background-image: url("images.png");
			background-size: 30px 30px; */
		}
	</style>
</head>
<body>
	<h1 class="content-before">标题前的内容</h1>
</body>
</html>